Well pump



Nov. 28, 1944.`

J. E. LUCAS WELL PUMP 2 Sheets-Sheet l Filed Feb. 3, 1944 J. E. LUCAS Nov. 28, 1944.v

WELL PUMP Filed Feb. 3, `1944 2` sheets-sheet 2,

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FIG.3

6C* INVENTOR.

Patented Nov. 28,11944 y naar 2,363,603 Y l j WELL PUMP l r l I Jens E. Lucas, oklalioma'oamokla Appli-canori February s, 1944,' rseriailno. "520;939

'2 claims. (ci. 10a-179) `VMy invention `relates to well pumps, and more particularly to reciprocating pumps for-oil wells operated from the earths surface "byv a sucker rod string.

Oneobject of` the inventionis to provide a pump `of this class which produces through the Well casing, in eontradistinction to'fthose which produce through `a. string of well tubing within the casing. l

Arurther object is to `provide an ou wen :pump

adapted to Vbe lowered into the Well on a tubing y string, "to `be set -by,n`1.anipulationV of the tubing string, and in which the tubing string acts as a sucker-'rod guide `for eliminating side-slap or whip in the sucker-rod string.

`Another object is to `provide `a 'reciprocating oil 'well pump and associated tubing string, which will eliminate a large portion of the present day` rod tati-'gue which is usually caused 'by the distortion of the 'rod string down stroke. l

l lstill further object is to reduce lthe `Wall friotion on the upwardly `travelling'column of oil, since its velocity is reduced when the oilis dis-- charged "from l a `comparatively small areapump piston ychamber to a larger 'area well casing.

*Other objects and `advantages `will be apparent from the following description when taken {inconnection withthe accompanying two-sheet drawings, wherein:` l l l ZFigure 1 is 1an lelevational view, partially in 'vertical section, 'of `a Ilcasedwell, the fdevice "of the present inventionV being rshown operatively installed therein;

.l -Figure 2 is `a Vertical 'sectional view of the device operatively installed in a well casing, the operating `'parts being `shown as they appear 'at upper end ofthe pump stroke; l

Figure 3 is an` elevationalview of the 'device within a well casing, the partsbeingshown as they appear while being lowered into the well, lorbefore the packer has `been set in the casing; and,`

Figure 411s a view similar to Fig. lf3 with the 'device `set` vin the casing `and the packer `exlpanded. e I l V f Like characters of Preference designate' like parts in all the gures. l

In the drawings:

I The reference numeral Iindicates, asawhole,

a msual `well v"casing 'extending vfrom (the earths surface 2, to lanreil producing `'stratum "3there'1 The lower end `of thei casing is "ordinarly cemented lin place, but for the present purpose, this feature has not been shown."

in the tubing on the` upper yend ofthe `casing `I has `a suitable `head '4, landfthere'below is 1alatera'l outletl pipe 5 for oil, The pump structure per se is lowered through the casing F'I to a point above the `producing stratum 3 by being attached to thelower end of a tubing string 6. The tubingV string 6, at itsupper end, passes' through and extends' Aabove thelheadl' l Tnelpump structure per se and its associated packer mechanism consists 'substantially of a head I0 (Fig. `2) the upper'tubular end portion 1I of which is threadedly engaged with the lower section I2 of the tubing stringV 6. The lower end portion 'I4 `of'the head VII) is also tubular in form andi exteriorly threaded to receive the upper end of' Ia sleeve I5. The lower end of tlie sleeve l5 is threadedlyengaged with a` comparatively heavy metal `pacler-head I6 `about `which is rmly'lattachedthe upper `end of an expandable packer-sleeve I1 made-of suitable material, for

instance canvas, rubberor a combinationthere-` of. vThe packer head I6 is annular inrform and its bore *is threaded to "receive the upper endof a 'tubular` sleeve I8 'which extends downwardly through and 1 below the, packer Asleeve 4 Ig'l.

The lower end offtheresilient packer sleeve I1 is ,firmly attachedto the upper end of a suit able slip expanding 4mandrel I9 having aiconically` tapered exterior lower end portion 20. The mandrel I9 is alsotubular in form, and its bore slidably .receives the `lower portion of the above mentioned sleeve I8. The exterior diameter of the `sleeve I8 and lthe diameter' ofthe boreof thelmandrel t9 are such that thessleeve bare workingt in the mandrel.`

The 'lower end :of fthe borefof the mandrel I9 has a 'threaded wall which receives t'heupper 4endrof the tubing section 2l which extends therebelow any desired distance. There may be any desirednumber of tubing `sections attached together below the section 2|, inwhich case the lowermost one would -beattachedby a coupling V l 22 to the upper 'end of `a conventional pump barrel .23.

`22 "to fthe tubing section 2|. n n

-Bel'ow the barrel 23 and "attached to the lower end thereof., is a plurality of perforatedmud-n "anchors 24 havingthereinla conventional Ldownable `.'lslot 21 in its 'lower end. The J-slot f2 l has 4"a "laterally @attending portion i2@ fwithi-n Ishasa l In the lpresentfinstance (Fig. 2`),\` the barrel 23`iscshown as fattached `by the coupling when the stud 2'9 is engaged within the iaterally extending portion 28 of the J-slot 21, the slips 3|- are held in a position below the tapered portion of the mandrel I9' (Fig. 3).

The J-tool sleeve 26 is also exteriorly equipped with a plurality of radially spaced springs 32 which are bowed outwardly intermediate their ends to frictionally engage` the vinside surfacer of the well casing I.

When it is desired to set the packer vstructure in the casing, the tubing string 6 is rotated toward the left hand. The frictional engagement of the springs 32 `with the casing I prevents asimilar rotation of the J-tool sleeve 26; and consequently the stud 29 out of the lateral portion 28 of the J-slot 21 (Fig. 4). When this is done, the tubing string is lowered slightly, the

J-tool sleeve 26 remaining stationary vdue to the action of the springs 32. Downward movement of the tubing string 6 permits the tapered lportion 20 of the mandrel I9 to enter the slips 3l and expand them into positive gripping engagement with the casingfI (Fig. 4). y

Furthery downward movement of the tubingy string 6 moves the packer-head I6 toward the mandrel I9 and, throughcompression, expands the packer sleeve I'I Iinto sealing engagement with the casing I. `During this downward movement, the tubular sleeve I8 which depends from vthe packer-head I 6` slides downwardly Ithrough .theV mandrel III.

Since Amost oil wells have suicient natural bottomhole pressure to cause the, oil to rise some distance in ythe casing I the packer will preferably be set at some desired point below the surface' of the column of oil normally standingin the casing, and when expanded, the packer will separate the upper and lower portions of this column. The separated upper and lower portions of this oil column are indicated respecv tively (Figs, 1, 2 and 4) by the reference numerals 35 and 3|.` v

yAs `a means for pumping oil from the lower oil column portion 36 to a point in the casing above the packer sleeve Il, and for delivering the pumped oil into the upper oil column portion 35, the following described elements are provided.

wardly closing check valve 4I. The check valve 4I has a working fit around the sucker rod string, and that section of the rod string which passes through the valve 4I is accurately machined so as to have the valve. l

The central portion of the body I0 just above the valve seat 40 has two open sides which permit pumped oil to exhaust from the body I0 into the casingl and comminglewith the oil column portion therein.

The upper tubular portion II ofthe body III has resilient packing elements 42 and 43 around the sucker-rod section passing therethrough, so that no oil will enter the lower end of the tubing string 6. The packing elements 42 and 43 may be of 'any usual type, and should be arranged in connection with common and well known packing gland thrust nuts, not shown. A helical spring 44 surrounds the ysucker rod withinthe head II),` and bears against vthe (valve 4I to normally urge it` toward 'apsealing position upon its valve Vseat element40.

In' operation, the parts of the pumping and packing mechanisms arefassembled together'as shown `in Fig. 2,'and the assembly is lowered into `the well casing Iv on thelower section ofthe tubing string ,toa desired position. The packenis expanded in the manner above described herein. The,` portion ofthe sucker rod string shown in Fig.V 2 will be lowered-withthe assembled appa- A usual sucker rod string 3l vextends downn wardly from above the earths ,surface through the casing `head 4, tubing string 6, head` I Il, sleeve I5', packer head I6 and sleeve I8, tubing section 2II coupling 22,r and into the pump barrel 23. A

suitable hollow pump piston 38 is provided with- 1 in the barrel 23, and this piston is provided with aconventional downwardlyclosing checkvalve 39, commonly termed the traveling valve. The piston 38 is moved upwardly and .downwardly in the barrel 23 by vertically reciprocating the sucker rod string by conventional power driven apparatus, not shown,which is connected to its upper end.

Within the lowerportion I4 of the head` I0 is .provided a rigidly Amounted Ltubular valve seat element 40, and ksurrounding the sucker rod string 3lwithin the head II)` is providedadownratus,: and tubing sections and sucker rod sections'will `be consecutively added to the respective stringsv at the earths surface as the lowering process continues. i :During the lowering operation, the pumppiston 38 will be at the upper end of its stroke, and the valves 25, 39 and4l will all open to permit downward passage of `the apparatus through-the oil column in the casing.

`After the packer has been set, the rrodgstring will, be dropped to the lower end of its stroke ,and` the foot valve 25 willI thereby be closed. Subsequentupperl movement of the sucker rod string. and pump piston 38 will cause the traveling valve 39v to close, and oil in the pump 4barrel thereabove will be raised..r `The Ioil `thus -being raised will force theouppervalve 4Iopen,` and `the oil will be discharged from the` open sides of the head I0 into the casing |above1thepacken The suction created by the upperstroke ofthe piston willV open the foot valve 25 so'thatthe a suitable and well known releasable connecting c .elementAE-so that the rod string thereabove may be released by a partial rotation thereof." Such a connection'i-is commonly usedin, sucker rod strings. f i Y It is further pointed out that iby discharging Athe pumped oil vfromy the'relati-vely small area valve seat; element Ilinto the larger area casing I, the wall friction of the-column 35 is materially reduced below thatnormally present in pumpingV apparatus.which-,produces through Aa tubing string. -Y Y t l. .Lf

a perfect working t with Also, that since no oil is produced through the present tubing-string 6, it can be made of smaller diameter than standard production tubing. This is possible because it is not necessary in the present structure for oil to pass upwardly in the tub-l ing string past the enlarged rod couplings.

Attention is further called to the fact that by more closely surrounding the sucker rod string, l

a pump unit adapted to be positioned in a Well,

packer means adapted to form a seal between the unit and the well walls, and with a pumpactuatving sucker rod string extending from the earths surface downwardly through the packer means to the pump unit, of: a head above the packer having openings for discharging pumped fluid from the pump unit into the well; an annular Valve seat in said head below said openings; a downwardly closing valve surrounding a section of the n rod string and adapted to close upon said seat;

a tubing string surrounding said rodI string and extending from said head to the earths surface; and packing in said head around said rod section above said openings forpreventing entry of said fluid into the tubing string.

2. In pumping apparatus, the combinationwith a pump unit adapted to be positioned in a well, packer means adapted to form a seal between the unit and the well walls, and with a pump actuating sucker rod string extending from the earths surface downwardly through the packer means to the pump unit, of: a head above the packer havling openings for discharging pump fluid from the pump unit into the well; an annular valve seat in said head below said openings; a downwardly closing valve surrounding a section of the rod -string and adapted to close upon said seat; and

a tubing string surrounding said rod string and extending from said head to the 'earths surface.

` JOHN E.. LUCAS. 

